function [linet1,linet2]=topsin(lasheader)
%
% [linet1,linet2]=topsin(lasheader)
%
% linet1 is the line in the lasheader with the first top
% linet2 is the line in the lasheader with the last top
%
% NOTE: This SOFTWARE may be used by any individual or corporation for any purpose
% with the exception of re-selling or re-distributing the SOFTWARE.
% By using this software, you are agreeing to the terms detailed in this software's
% Matlab source file.

% BEGIN TERMS OF USE LICENSE
%
% This SOFTWARE is maintained by the CREWES Project at the Department
% of Geology and Geophysics of the University of Calgary, Calgary,
% Alberta, Canada.  The copyright and ownership is jointly held by
% its 'AUTHOR' (identified above) and the CREWES Project.  The CREWES
% project may be contacted via email at:  crewesinfo@crewes.org
%
% The term 'SOFTWARE' refers to the Matlab source code, translations to
% any other computer language, or object code
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% Terms of use of this SOFTWARE
%
% 1) This SOFTWARE may be used by any individual or corporation for any purpose
%    with the exception of re-selling or re-distributing the SOFTWARE.
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% END TERMS OF USE LICENSE
  [nlines,nchar]=size(lasheader);
%
% search for TOPS 
%
  linet1=-1;
  for line=1:nlines
	  str = lasheader(line,:);
	  if(strcmp(str(2:5),'TOPS'))
	    linet1=line+1;
	  end
  end
  if(linet1 ~= -1)   %found some TOPS
    line=linet1-1;
    str='yyy';
    while ( (strcmp(str(1),'~') == 0) & (strcmp(str(1),'#') == 0) )
     	  line=line+1;
	  str = lasheader(line,:);
    end
    linet2=line-1;    %last top
  else     %no TOPS found, so return location of ~Curve Info
	   % for both l1 and l2
    for line=1:nlines
	  str = lasheader(line,:);
	  if(strcmp(str(1:9),'~Curve In'))
	    linet1=line;
	    linet2=line-1;
	  end
    end
  end
  if(linet1 == -1)
    linet1=1;
    linet2=0;
  end